Made from paper, these signs are waterproof, sun resistant, and rainproof to maintain bright colors and visibility for years in both indoor and outdoor environments It is better to use the color red to get their attention and stop in their tracks This do not enter sign will help keep your limited areas off limit These signs provide immediate recognition from a distance to effectively communicate limited access and enhances security Bold and Direct: Do Not Enter Sign Each package includes six stickers to help keep your guests out of areas they are not supposed to be in Simply stick these signs to any door Wide Application Ranges: Ideal for factories, warehouses, construction site, parking lots, private properties, emergencies exits, and single way roads